In an exciting session at the University of Sydney, Dr. Phil dives into the concept of atmospheric pressure and how it affects us. He explains the huge pressure that the air around us exerts on our bodies and shows how we can see this in action through a cool experiment.
Dr. Phil starts by telling us that we are all under a lot of pressure—about 10,000 kg from the air around us! This pressure comes from the weight of the air above us, which stretches up about 20 kilometers into the sky. Imagine being at the bottom of an “ocean of air” that constantly pushes down on us.
Even though this pressure is huge, we don’t feel squished. Why? Because the pressure inside our bodies matches the pressure outside. This balance keeps us from getting crushed or expanding, allowing us to go about our daily lives without any problems.
To show how strong atmospheric pressure is, Dr. Phil suggests a dramatic experiment. He jokes about “scooping out” someone’s insides to see the effects, but quickly moves on to a safer lab experiment.
Dr. Phil uses a drum to represent a person. In the experiment, he heats water inside the drum to create steam, which pushes out the air. As the water boils, it turns into vapor, replacing the air inside the drum.
Once the air is out and the drum is sealed, it’s time to cool it down. As the steam turns back into water, the pressure inside the drum drops a lot. Dr. Phil puts on safety glasses and gloves, showing how important safety is during experiments.
As the experiment continues, something amazing happens. When the pressure inside the drum gets low enough, the outside atmospheric pressure crushes the drum suddenly. This surprising reaction shows just how powerful atmospheric pressure can be.
The experiment ends with a clear demonstration of atmospheric pressure’s effects on a closed space. Dr. Phil’s fun and educational presentation not only teaches us about the science of pressure but also gives us a memorable picture of the forces that are always at work in our world.
Try this at home! Fill a plastic bottle with hot water, then pour it out and quickly cap the bottle. Watch as the bottle collapses inward. This demonstrates how the pressure inside the bottle decreases, allowing atmospheric pressure to crush it. Discuss with your classmates why the bottle changes shape.
Build your own barometer using a glass jar, a balloon, and a straw. Cut the balloon and stretch it over the jar’s opening, securing it with a rubber band. Tape a straw on top of the balloon. As atmospheric pressure changes, the straw will move. Record the straw’s movement over a week and discuss how it relates to weather changes.
Research how atmospheric pressure changes with altitude. Use a sealed plastic bag and a straw to simulate this. Suck out some air from the bag and seal it. Notice how the bag shrinks, similar to how pressure decreases as altitude increases. Discuss with your classmates why this happens and how it affects breathing at high altitudes.
Use an online simulation to explore how atmospheric pressure affects different objects. Adjust variables like temperature and altitude to see how they change the pressure. Share your findings with the class and explain how these factors influence weather patterns and human activities.
Identify and list five examples of atmospheric pressure affecting everyday objects or activities, such as a vacuum cleaner or a syringe. Present your examples to the class and explain the science behind each one. Discuss how understanding atmospheric pressure can be useful in real life.
Atmospheric – Relating to the layer of gases surrounding the Earth – The atmospheric pressure decreases as you climb higher up a mountain.
Pressure – The force applied perpendicular to the surface of an object per unit area – When you dive deep into the ocean, the water pressure increases significantly.
Experiment – A scientific procedure undertaken to test a hypothesis – In our science class, we conducted an experiment to see how different materials affect the speed of a rolling ball.
Air – The invisible gaseous substance surrounding the Earth, a mixture mainly of oxygen and nitrogen – The balloon rose into the air because it was filled with helium, which is lighter than air.
Steam – The vapor into which water is converted when heated, forming a mist of minute water droplets in the air – When water boils, it turns into steam and rises into the air.
Water – A transparent, odorless, tasteless liquid that forms the seas, lakes, rivers, and rain – Water is essential for all known forms of life and covers about 71% of the Earth’s surface.
Drum – A cylindrical container used for storing or transporting liquids – In the science lab, we used a metal drum to safely store the chemical solutions.
Safety – The condition of being protected from or unlikely to cause danger, risk, or injury – Wearing goggles and gloves is important for safety during a chemistry experiment.
Science – The systematic study of the structure and behavior of the physical and natural world through observation and experiment – Science helps us understand how the universe works, from the smallest particles to the largest galaxies.
Forces – Influences that can change the motion of an object, typically described by magnitude and direction – The forces acting on a falling object include gravity and air resistance.
